From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753177Ab2DPK7N (ORCPT ); Mon, 16 Apr 2012 06:59:13 -0400 Received: from e28smtp01.in.ibm.com ([122.248.162.1]:51704 "EHLO e28smtp01.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753095Ab2DPK7L convert rfc822-to-8bit (ORCPT ); Mon, 16 Apr 2012 06:59:11 -0400 From: "Aneesh Kumar K.V" To: Sasha Levin Cc: davem@davemloft.net, ericvh@gmail.com, jvrao@linux.vnet.ibm.com, rusty@rustcorp.com.au, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, davej@redhat.com Subject: Re: [PATCH] 9p: disconnect channel when PCI device is removed In-Reply-To: References: <1334353716-19483-1-git-send-email-levinsasha928@gmail.com> <87iph118pd.fsf@skywalker.in.ibm.com> User-Agent: Notmuch/0.11.1+346~g13d19c3 (http://notmuchmail.org) Emacs/23.3.1 (x86_64-pc-linux-gnu) Date: Mon, 16 Apr 2012 16:29:01 +0530 Message-ID: <87ehrodjt6.fsf@skywalker.in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT x-cbid: 12041610-4790-0000-0000-00000233EF27 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sasha Levin writes: > On Sun, Apr 15, 2012 at 2:27 PM, Aneesh Kumar K.V > wrote: >> Sasha Levin writes: >> >>> When a virtio_9p pci device is being removed, we should close down any >>> active channels and free up resources, we're not supposed to BUG() if there's >>> still an open channel since it's a valid case when removing the PCI device. >>> >>> Otherwise, removing the PCI device with an open channel would cause the >>> following BUG(): >>> >> ... >> >>> diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c >>> index 3d43206..5af18d1 100644 >>> --- a/net/9p/trans_virtio.c >>> +++ b/net/9p/trans_virtio.c >>> @@ -615,7 +615,8 @@ static void p9_virtio_remove(struct virtio_device *vdev) >>>  { >>>       struct virtio_chan *chan = vdev->priv; >>> >>> -     BUG_ON(chan->inuse); >>> +     if (chan->inuse) >>> +             p9_virtio_close(chan->client); >>>       vdev->config->del_vqs(vdev); >>> >>>       mutex_lock(&virtio_9p_lock); >> >> But an umount should have resulted in p9_virtio_close ? How are you >> removing the device ? Are you removing the device with file system >> mounted  ?. In that case may be we should return EBUSY ? > > I signal the underlying PCI device to remove (echo 1 > > /sys/devices/pci0000\:00/[...]/remove), we can't really prevent that > thing so we must clean up ourselves. What does that mean for the mounted file system ? What would happen to the pending fs operations in that case ? -aneesh